Eight-Channel Programmable Filter and Gain Signal Conditioning Plug-on VT1503A

Transcription

1 bus Eight-Channel Programmable Filter and Gain Signal Conditioning Plug-on VT1503A User s Manual The VT1503A manual also applies to Agilent/HP E1413Bs as E1413 Option 13. Enclosed is the User s Manual for the VT1503A Signal Conditioning Plug-on. Insert this manual in your VT1413C, Agilent/HP E1313 or VT1415A manual behind the Signal Conditioning Plug-ons divider. Copyright VXI Technology, Inc., 2003 Manual Part Number: Printed: June 16, 2003 Printed in U.S.A.

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3 VT1503A Eight-Channel Programmable Filter and Gain Signal Conditioning Plug-on Introduction About this Manual Installation Identifying the Plug-on The VT1503A is a Signal Conditioning Plug-on that provides eight programmable low-pass filters with cutoff frequency settings of 2, 10 and, 100 Hertz (Hz), as well as a 1.5 khz pass-through mode (filter ). The eight programmable input amplifiers provide gains of 1, 8 and 64. Also provided is input over-voltage protection and open transducer detection on each channel. Except where noted, all references to the VT1413C apply to the Agilent/HP E1313 and VT1415A. This manual shows you how to control the Signal Conditioning Plug-on (SCP) using SCPI commands as well as Register-Based commands, and explains the capabilities of this SCP. Finally, it covers specifications for this SCP. The contents of this manual are: Installation...3 Identifying the Plug-on....3 Connecting To The Terminal Module...4 Programming With SCPI Commands....6 Programming With Register Commands...10 Specifications...12 Installation for this Plug-on is common to several others and is covered in Chapters 1 and 2 of your VT1413C or Agilent/HP E1313 manual. You ll find the VXI Technology part number on the connector side of the SCP to the left of the serial number bar code. For the VT1503A, the part number is : VT1503A Introduction VT1503A Amplifier+Filter SCP 3

4 Connecting To The Terminal Module This section shows how to make connections to the Terminal Module. The SCP connections for the Terminal Modules are shown on the stick-on labels that came with the SCP. Use the appropriate label for the type of Terminal Module you have. The connections and appropriate stickers are as follows: For VT1413C and above Terminal Modules, use stickers for VT1503A SCPs. The connections are shown in Figure 1. For Agilent/HP E1313 Terminal Moduless, use stickers for VT1503A SCPs. The connections are shown in Figures 2 and 3. For Agilent/HP E1413B and below Terminal Modules, use stickers for Agilent/HP E1413 Option 13 SCPs. The connections are shown in Figure 4. Figure 1 VT1503A C-Size Terminal Module Connections 4 VT1503A Amplifier+Filter SCP Connecting To The Terminal Module

5 Figure 2 VT1503A B-size Terminal Module Connections (Ch 00-31) Figure 3 VT1503A B-size Terminal Module Connections (Ch 32-63) Figure 4 Agilent/HP E1413 Option 13 Terminal Module Connections Connecting To The Terminal Module VT1503A Amplifier+Filter SCP 5

6 Programming With SCPI Commands The SCPI commands shown here are covered in Chapters 3 and 5 of your VT1413C or Agilent/HP E1313 manual. This section will relate those commands to the parameter values which are specific to this Plug-on. Checking the ID of the SCP To verify the SCP type(s) installed on the VT1413C or Agilent/HP E1313 use the SYSTem:CTYPe? (@<channel>) command. The channel parameter specifies a single channel in the channel range covered by the SCP of interest. The first channel number for each of the eight SCP positions are; 0,8,16,24,32,40,48 and 56. The value returned for the SCP in an Agilent/HP E1413B is: HEWLETT-PACKARD,E1413 Opt 13 8-Channel Amp+Filter SCP,0,0 The returned value for the SCP in a VT1413C or Agilent/HP E1313A is: HEWLETT-PACKARD,E Channel Amp+Filter SCP,0,0 To determine the type of SCP installed on channels 0 through 7 send SYST:CTYP? (@100) query SCP ch 0 enter statement here enter response string Setting the Filter Cutoff Frequency To set the channel cutoff frequency use the INPut:FILTer[:LPASs]:FREQuency <cutoff>, (@<ch_list) command. The cutoff parameter can specify 2, 10, 100, MIN or MAX. MIN will specify 2 Hz while MAX will specify 100 Hz. To set channels 0 through 15 and 24 to the 2 Hz cutoff frequency and channels 16 through 23 to the 100 Hz cutoff frequency send INP:FILT:FREQ 2, (@100:115,124) INP:FILT:FREQ 100, (@116:123) send separate command per cutoff frequency or to combine into a single command message INP:FILT:FREQ 2, (@100:115,124);FREQ 100, (@116:123) NOTE The *RST and Power-On condition for cutoff frequency is MIN for all channels. 6 VT1503A Amplifier+Filter SCP Programming With SCPI Commands

7 Querying the Filter Cutoff Frequency To query any channel for its cutoff frequency use the INPut:FILTer[:LPASs]:FREQuency? command. The INP:FILT:FREQ? command returns the numeric cutoff value currently set for the channel specified. The channel parameter must specify a single channel. To query the cutoff frequency of channel 6 send INP:FILT:FREQ? (@106) query channel 6 enter statement here returns 2, 10, or 100 Enabling and Disabling the Filter To enable and disable channel filters use the INPut:FILTer[:LPASs][:STATe] <enable>, (@<ch_list) command. The enable parameter can specify ON or To enable channels 0 through 15 and 20 to filter, send INP:FILT ON, (@0:115,120) channels filtering as set by INP:FILT:FREQ To disable channels 0 through 8 send INP:FILT, (@100:108) channels 0-8 are now in pass-through mode NOTES 1) INP:FILT ON is the *RST and Power-On condition for all filter channels. 2) INP:FILT has a low-pass filter characteristic of approximately 1.5 khz and limitations to signal levels. It is intended primarily for diagnostic use. Querying the Filter State To query any channel to determine if it is enabled or disabled use the INPut:FILTer[:LPASs][:STATe]? (@<channel>) command. The INP:FILT? command returns a 0 if the channel is or a 1 if the channel is ON. The channel parameter must specify a single channel. To query the filter state of channel 2 send INP:FILT? (@102) query channel 2 enter statement here returns 0 or 1 Programming With SCPI Commands VT1503A Amplifier+Filter SCP 7

8 Setting the Amplifier Gain To set the channel gain use the INPut:GAIN <gain>, command. The gain parameter can specify 1, 8, 64, MIN or MAX. MIN specifies 1 while MAX specifies 64. Note that the gain choices for this SCP are multiples of 8 to complement the VT1413C or Agilent/ HP E1313 s A/D range choices which are multiples of 4. The following table shows the gain and range combinations. A/D Range SCP Gain 16 V (A/D gain 1) 4 V (A/D gain 4) 1 V (A/D gain 16) 0.25 V (A/D gain 64) V (A/D gain 256) , ,024 4,096 not allowed To set channels 32 through 47 and 63 to a channel gain of 8 and channels 48 through 55 to a channel gain of 64 send INP:GAIN 8, (@132:147,163) INP:GAIN 64, (@148:155) send separate command per gain factor Querying the Amplifier Gain To query any channel to determine its gain setting use the INPut:GAIN? (@<channel>) command. The INP:GAIN? command returns the current gain value for the specified channel. The channel parameter must specify a single channel. To query the gain setting of channel 8 send INP:GAIN? (@108) query channel 8 enter statement here returns 1, 8, or 64 Detecting Open Transducers This SCP provides a method to detect open transducers. When Open Transducer Detect (OTD) is enabled, the SCP injects a small current into the HIGH and LOW input of each channel. The polarity of the current pulls the HIGH inputs toward +17 volts and the LOW inputs towards -17 volts. If a transducer is open, measuring that channel will return an over-voltage reading. OTD is available on a per SCP basis. all eight channels of an SCP are enabled or disabled together. See Figure 5 for a simplified schematic diagram of the OTD circuit. 8 VT1503A Amplifier+Filter SCP Programming With SCPI Commands

9 Signal Input Signal Conditioning Plug-on Multiplexer High High +17V 100M 3K Gnd. 100M 3K -17V Low Low Figure 5 Open Transducer Detect Circuit NOTES 1) When OTD is enabled, the inputs have up to 0.2 µa injected into them. If this current will adversely affect your measurement, but you still want to check for open transducers, you can enable OTD, make a single scan, check the CVT for bad measurements, then disable OTD and make your regular measurement scans. The specifications apply only when OTD is off. 2) When Filtering is enabled, allow 15 seconds or the filter capacitors to charge before checking for open transducers. To enable or disable Open Transducer Detection, use the DIAGnostic:OTDetect <enable>, (@<ch_list>) command. The enable parameter can specify ON or An SCP is addressed when the ch_list parameter specifies a channel number contained on the SCP. The first channel on each SCP is: 0, 8, 16, 24, 32, 40, 48 and 56 To enable Open Transducer Detection on all channels on SCPs 1 and 3: DIAG:OTD ON, (@100,116) 0 is on SCP 1 and 16 is on SCP3 To disable Open Transducer Detection on all channels on SCPs 1 and 3: DIAG:OTD, (@100,116) Programming With SCPI Commands VT1503A Amplifier+Filter SCP 9

10 Register Based Programming The register-based commands shown here are covered in Appendix D of the VT1413C or Agilent/HP E1313 manual. You should read that section first to become familiar with accessing registers and executing Register-Based Commands. This section will relate those commands to the parameter values which are specific to this Plug-on. When Register Programming an SCP most communication is through the Signal Conditioning Bus. For that you will use the Register Commands: SCBWRITE <regaddr> <regvalue> and SCBREAD? <regaddr> VT1503A Register Map Read (returned value) Write( <regvalue>) SCP Register <regaddr> Value SCP ID (E0E0 16) Whole SCP Reg 0 00ppp SCP Gain Scale (XXX3 16) Whole SCP Reg 1 00ppp Channel Gain (XXX0 16=1, XXX1 16=8, XXX2 16=64) Channel Reg 1 01pppccc001 2 Channel Frequency (XXX0 16=2Hz, XXX1 16=10Hz, XXX2 16=100Hz,XXX3 16=Straight Through) XX=don t care Channel Reg 2 01pppccc010 2 ppp=plug-on ccc=scp channel In addition you will access bits in the Card Control register to control Open Transducer Detection. Checking ID of SCP Setting the Filter Cut-Off To query an SCP for its ID value, write the following value to Parameter Register 1: ( SCP number) Then write the opcode for SCBREAD? ( ) to the Command Register. The ID value will be written to the Query Response Register. To set the filter cut-off frequency for an SCP channel, write the following SCP channel address to Parameter Register 1: 200 ( SCP number) 40 ( SCP channel number) Write one of the following cut-off values to Parameter Register 2: for 2Hz, for 10Hz, for 100Hz, for Straight Through Then write the opcode for SCBWRITE ( ) to the Command Register. 10 VT1503A Amplifier+Filter SCP Register Based Programming

11 Setting the Amplifier Gain Detecting Open Transducers To set the amplifier gain for an SCP channel, write the following SCP channel address to Parameter Register 1: 200 ( SCP number) 40 ( SCP channel number) Write one of the following gain values to Parameter Register 2: for 1, for 8, for 64 Then write the opcode for SCBWRITE ( ) to the Command Register. Open Transducer Detection (OTD) is controlled by bits in the Card Control Register. For more information on OTD see Figure 1. Card Control Register (Base ) PSI Pwr Reset FIFO Mode unused FIFO Clear VPPEN A24 Window Open Transducer Detect Writing a one (1) to a bit enables open transducer detect on that signal conditioning module. Writing a zero (0) to a bit disables open transducer detect. Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 SCP 7 SCP 6 SCP 5 SCP 4 SCP 3 SCP 2 SCP 1 SCP 0 Register Based Programming VT1503A Amplifier+Filter SCP 11

12 Specifications These specifications for the VT1503A reflect the combined performance of the VT1413C or Agilent/HP E1313 and the VT1503A Signal Conditioning Plug-on. These specifications are not to be added to those presented in the VT1413C Agilent/HP E1313 User s Manual. General Specifications SCP Current Requirements (in Amps) 5Vmax 24Vtyp 24Vmax -24Vtyp -24Vmax Measurement ranges DC Volts Temperature Resistance Strain ±3.9 mv to ±16V FS Thermocouples to C Thermistors - (Opt 15 required) -80 to +160 C RTD s - (Opt 15 required) -200 to +850 C (Opt 15 required) 128 to 131 K FS 25,000 µe or limit of linear range of strain gage Maximum input voltage (Normal mode plus common mode) Operating: < ±16 V peak Damage level: > ±42 V peak Maximum common mode voltage Operating: < ±16 V peak Damage level: > ±42 V peak Normal mode rejection 2 Hz Filter 10 Hz Filter 100 Hz Filter Filter 2 Hz Hz > Hz Hz > Hz Hz khz approx -3 db Common mode rejection (0-60 Hz) Gain X1 Gain X8 Gain X64 >-100 db >-116 db >-132 db Input impedance 100 M 10% (each differential input to ground) Maximum tare cal offset (Maximum tare offset depends on A/D range and SCP gain) A/D range ±V F.Scale Offset V Gain x1 Offset V Gain x8 Offset V Gain x N/A 12 VT1503A Amplifier+Filter SCP Specifications

13 Measurement accuracy DC Volts (90 days) 23 C±1 C (with *CAL? done after 1 hr warm up and CAL:ZERO? done within 5 min.). If autoranging is ON, add ±0.02% FS to accuracy specifications. For Agilent/HP E1313, multiply Noise Spec. by 1.4. Gain X1 Range ±V FS Linearity % of rdg Offset Error 2 Hz 10 Hz 100 Hz Filt Off Noise 3 sigma Noise* 3 sigma % 13 µv 9.5 µv 6.8 µv 6.3 µv 45 µv 26 µv % 15 µv 12.5 µv 11.2 µv 10.8 µv 63 µv 31 µv % 33 µv 31.8 µv 31.3 µv 31.2 µv 112 µv 93 µv % 123 µv 122 µv 122 µv 122 µv 450 µv 366 µv % 488 µv 488 µv 488 µv 488 µv 1.8 mv 1.5 mv * [SENSe:]FILTer[:LPASs][:STATe] ON (max scan rate rdgs/sec/channel) Temperature Coefficients: Gain - 15 ppm/ C after *CAL?. Offset - Add tempco + fixed offset to offset above Temp 0-30 C C C Tempco 0.16 µv/ C 0.18 µv/ C 0.39 µv/ C 2 Hz 13 µv 31 µv 10 Hz 9 µv 22 µv 100 Hz 1.1 µv 6.4 µv Filt Off 0.2 µv µv Gain X8 Range V FS Linearity % of rdg Offset Error 2Hz 10Hz 100Hz Filt Off Noise 3 sigma Noise* 3 sigma % 4.6 µv 4.2 µv 3.8 µv 3.7 µv 5.8 µv 4.9 µv % 4.8 µv 4.6 µv 4.4 µv 4.3 µv 6.9 µv** 5.9 µv** % 6 µv 5.3 µv 5 µv 4.9 µv 14 µv 12 µv % 16 µv 16 µv 16 µv 16 µv 56 µv 46 µv % 61 µv 61 µv 61 µv 61 µv 225 µv 188 µv * [SENSe:]FILTer[:LPASs][:STATe] ON (max scan rate rdgs/sec/channel) ** 7.4 µv and 6.3 µv when temp >= 40 C Temperature Coefficients: Gain - 15 ppm/ C after *CAL?. Offset - Add tempco + fixed offset to offset above Temp 0-30 C C C Tempco 0.16 µv/ C 0.18 µv/ C 0.39 µv/ C 2 Hz 4.3 µv 13 µv 10 Hz 2.7 µv Hz 1 µv 6.2 µv Filt Off 0.2 µv 0.8 µv Gain X64 Range V FS Linearity % of rdg Offset Error 2Hz 10Hz 100Hz Filt Off Noise 3 sigma Noise* 3 sigma % 2.9 µv 2.3 µv 2.1 µv 2.1 µv 1.6 µv** 1.3 µv** % 3 µv 2.4 µv 2.2 µv 2.2 µv 2.2µV*** 1.9µV*** % 3.5 µv 3 µv 2.9 µv 2.9 µv 7 µv 5.7 µv % 8.2 µv 8 µv 8 µv 8 µv 28 µv 23 µv * [SENSe:]FILTer[:LPASs][:STATe] ON (max scan rate rdgs/sec/channel) ** 1.9 µv and 1.7 µv for 100 Hz Filter *** 2.5 µv and 2.2 µv when temp >= 40 C Temperature Coefficients: Gain - 15 ppm/ C after *CAL?. Offset - Add tempco + fixed offset to table above Temp 0-30 C C C Tempco 0.16 µv/ C 0.18 µv/ C 0.39 µv/ C 2 Hz 1.1 µv 6 µv 10 Hz 0.2 µv 1.4 µv 100 Hz 0.1 µv 0.6 µv Filt Off 0.1 µv 0.6 µv Specifications VT1503A Amplifier+Filter SCP 13

14 Measurement accuracy Temperature (simplified specifications, see temperature accuracy graphs in the VT1413C or Agilent/HP E1313 manual for details) (90 days) 23 C ±1 C (with *CAL? done after 1 hr warm up and CAL:ZERO? within 5 min.). If autoranging is ON, add ±.02% FS to accuracy specifications. The temperature accuracy specifications include instrument and firmware linearization errors. The linearization algorithm used is based on the IPTS-68(78) standard transducer curves. Add your transducer accuracy to determine total measurement error. Thermocouples NOTE: ALL Thermocouple Specifications Use Gain X64 Type E A/D Filter -200 to 0 C 0 to 200 C 200 to 400 C 400 to 800 C 1.25 C 1.20 C 0.10 C C 0.12 C 0.10 C C 0.11 C Type EEXtended A/D Filter -200 to 0 C 0 to 200 C 200 to 800 C 800 to 1000 C 13.4 C 13.3 C 0.30 C 0.25 C 0.20 C 0.15 C 0.35 C 0.30 C Type J A/D Filter -200 to 0 C 0 to 280 C 280 to 600 C 600 to 775 C 1.50 C 1.47 C 0.10 C 0.11 C 0.15 C 0.15 C 0.17 C 0.15 C Type K A/D Filter -200 to 0 C 0 to 375 C 375 to 800 C 800 to 1400 C 2.25 C 2.70 C 0.15 C 0.15 C 0.20 C 0.17 C 0.25 C 0.25 C Type R A/D Filter 0 to 100 C 100 to 200 C 200 to 600 C 600 to 1000 C 1.40 C 1.40 C 0.75 C 0.70 C 0.45 C 0.40 C 0.30 C 0.30 C Type S A/D Filter 0 to 100 C 100 to 200 C 200 to 800 C 800 to 1750 C 2.85 C 2.85 C 1.35 C 1.80 C 0.70 C 0.65 C 0.65 C 0.55 C Type T A/D Filter -200 to -100 C -100 to 0 C 0 to 200 C 200 to 400 C 1.35 C 1.35 C 0.25 C 0.22 C 0.10 C 0.10 C 0.15 C 0.13 C * [SENSe:]FILTer[:LPASs][:STATe] ON (max scan rate rdgs/sec/channel) 14 VT1503A Amplifier+Filter SCP Specifications

15 Measurement accuracy Temperature (cont.) (simplified specifications, see temperature accuracy graphs in VT1413C or Agilent/HP E1313 manual for details) Thermistors 5 k Reference Thermistor Use Gain X8 A/D Filter 0 to 45 C 45 to 65 C 65 to 85 C C C C C C C 100 Reference RTD Use Gain X64 A/D Filter -125 to 70 C C C 100 RTD Use Gain X64 A/D Filter -200 to 75 C 75 to 300 C 300 to 600 C 600 to 970 C 0.08 C 0.07 C 0.21 C 0.18 C 0.27 C 0.25 C 0.37 C 0.35 C 2252 Thermistor Use Gain X8 A/D Filter 10 to 40 C 40 to 70 C 70 to 83 C 83 to 100 C C C C C C C C C 5 k Thermistor Use Gain X8 A/D Filter -10 to 20 C 20 to 40 C 40 to 65 C 65 to 85 C C C C C C C C C 10 k Thermistor Use Gain X8 A/D Filter 0 to 30 C 30 to 60 C 60 to 90 C 90 to 115 C C C C C C C C C Specifications VT1503A Amplifier+Filter SCP 15

16 Notes 16 VT1503A Amplifier+Filter SCP Specifications